const unsigned char SHAKE_1 = 0x01;
const unsigned char SHAKE_2 = 0x02;
const unsigned char SHAKE_3 = 0x03;
const unsigned char WAVE_1 = 0x04;
const unsigned char WAVE_2 = 0x05;
const unsigned char WAVE_3 = 0x06;
const unsigned char WAVE_4 = 0x07;
const int MAX_WAIT_TIME = 1000;
const int MAX_WAVE_TIME = 2000;
const unsigned char LAST = 0x20;
const unsigned char MIDDLE = 0x21;
const int MAX_LEN = 14000;
const int WIN_SIZE = 10;
const unsigned char NAK = 200;
const int serverPort = 8000;
const int clientPort = 10005;

unsigned char checksum(char* package, int len);